81 x 9 = 801. What must you do to make the this equation true?

I have no doors but I have keys, I have no rooms but I have space, you can enter but you can’t leave! What am I?

In the four images below, can you find the odd one out?

A thief is convicted in Mexico. He gets the death penalty. The judge allows him to say the last sentence to determine how the penalty will be carried out. If the thief lies, he will be hanged, if he speaks the truth he will be beheaded. The thief tells the last sentence and to everybody's surprise some minutes later he is set free because the judge cannot determine his penalty. What did the thief say?

Can you figure out the logic I used to decide the order of the following words:
gun, shoe, spree, door, hive, kicks, heaven, gate, line, den

If you drop a 15 kg iron bar and a 5 kg bag of cotton from a height of 50 meters which will reach the ground first?

What is the next number in this matchsticks series riddle?

Solve the mathematical equation in the picture below.

In a football game, Christina defeated Teresa by 2 - 0 but no man from either side scored. How can this be possible?

Can anyone tell me a word in the English dictionary which has a silent 'z'?